Hermetic Java: OnLoad_<libname> changes

[Magnus Ihse Bursie]

I've tried to extract the changes in the hermetic-java-runtime branch 
that relates to the OnLoad_<libname> changes. It turns out that it was 
some time since the last merge of master into this branch, so there were 
quite a few conflicts due to the changes in these areas lately.

I think I have solved the conflicts properly, and have opened a draft PR 
for transparency on what I'm working on: 
https://github.com/openjdk/jdk/pull/22694. However, I have not tested 
this code yet, nor do I think it is fit for review. This looks like a 
too hacky solution to be permanent. I'll try to clean it up a bit before 
moving the PR out of the draft state.

/Magnus